Fulfilling America’s Pledge

When President Trump walked away from the US target under the Paris Agreement, we knew states, cities, and businesses needed to pick up the mantle of climate leadership. But people wanted to know: what difference can these bottom-up initiatives make? Is America’s pledge still within reach despite the abdication of federal leadership? These are the questions that California Governor Jerry Brown and former New York City Mayor Mike Bloomberg immediately saw needed to be answered to prevent a loss of confidence in the Paris project as a whole.

Last year, we showed that states, cities, and businesses that continue to drive forward on climate action comprise more than half of the US economy and more than half of the US population. Since Bloomberg and Brown took that message to the world at last year’s United Nations climate conference in Bonn, the coalition has continued to swell. It now represents $11.4 trillion of economic output and 173 million Americans. If this coalition of the willing were a country, it would be the third-largest in the world.

The key question—does all this matter for future US emissions—took a little longer to answer. A team of researchers led by Rocky Mountain Institute and the University of Maryland spent almost a year building a novel modeling approach that combines the rigor of an integrated economy-wide model with the capability to integrate specific bottom-up actions led by states, cities, and businesses. The result is the most comprehensive picture to date of where US emissions are headed and how much progress real economy actors can drive without federal leadership.

The Fulfilling America’s Pledge report first models that current commitments, combined with market forces, are on track to drive US emissions to 17 percent below 2005 levels by 2025, roughly two-thirds of the way to the original US target. We provide a comprehensive survey of sector-specific actions across all 50 states, the largest 285 cities, and a wide number of businesses in order to assess the impact of climate actions. These actors have already adopted greenhouse gas emissions targets that could cut annual emissions by 500 million tons of CO2 from business-as-usual levels by 2025. State, city, and business clean-energy procurement policies (e.g., renewable portfolio standards) should increase demand for nonhydroelectric renewable generation to over 500 terawatt-hours (TWh) by 2025—enough to power 56 million homes for a year. Energy efficiency policies enacted by states, cities, and utilities could result in annual energy savings of over 200 TWh per year by 2025—saving enough energy to power 22 million homes for a year or to allow the closing of 37 coal power plants.

Moving on from current policies, we mapped out ten specific climate action strategies—high-impact, near-term, actionable measures—that could drive emissions down further, to 21 percent below 2005 levels by 2025. The key takeaway is that growing and deepening this real-economy coalition within realistic legal and political constraints has the potential to reduce emissions by more than 24 percent below 2005 levels by 2025, bringing the United States within striking distance of the US Paris pledge. To put that in global perspective, by 2025, the effect these cities, states and businesses can have on the health of the climate, building on progress achieved since 2005, is the same as eliminating the emissions of 100 countries.

Real-economy actors have the power to bring the nation to the brink of hitting the US target in 2025 without federal help. Best of all, they are already well on their way to doing so.